Adherence to fingolimod in multiple sclerosis: an investigator-initiated, prospective, observational, single-center cohort study

OBJECTIVES: Adherence to multiple sclerosis (MS) treatment is essential to optimize the likelihood of full treatment effect. This prospective, observational, single-center cohort study investigated adherence to fingolimod over the 2 years following treatment initiation. Two facets of adherence – implementation and persistence – were examined and compared between new and experienced users of disease-modifying treatments (DMTs). MATERIALS AND METHODS: Implementation rates were based on the proportion of days covered and calculated as percentages per half-yearly visits and over 2 years, captured through refill data, pill count, and self-report. Nonadherence was defined as taking less than 85.8% of prescribed pills. Implementation rates were classified as nonadherent (<85.8%), suboptimally adherent (≥85.8% but <96.2%), and optimally adherent (≥96.2%), including perfectly adherent (100%). Persistence, ie, time until discontinuation, was analyzed by Kaplan–Meier analysis. Reasons for discontinuation were recorded. RESULTS: The cohort included 98 patients with relapsing MS, all of whom received a dedicated education session about their medication. Of these 80% were women, 31.6% had fingolimod as first DMT, and 68.4% had switched from other DMTs. The mean implementation rate over 2 years was 98.6% (IQR(1–3) 98.51%–98.7%) and did not change significantly over time; 89% of measurements were in the optimally adherent category, 45.6% in the perfectly adherent category. There was one single occurrence of nonadherence. New users of DMTs were 1.29 times more likely to be adherent than experienced users (OR 1.29, 95% CI 1.11–1.51; P<0.001), but not more persistent. Nineteen of 98 patients discontinued fingolimod. CONCLUSION: The very high implementation rates displayed in this sample of MS patients suggest that facilitation by health care professionals in preserving adherence behavior may be sufficient for the majority of patients. Targeted interventions should focus on patients who are nonadherent or who stop treatment without intention to reinitiate.